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In: Mechanical Engineering

The circular fin of diameter D=1mm and length L=25.4mm, made of copper (k=400 W/m.K), are used...

The circular fin of diameter D=1mm and length L=25.4mm, made of copper (k=400 W/m.K), are used to enhance heat transfer from a surface that is maintained at temperature Tb=132 °C. and the rod has another end attached to a large surface which is maintained at Te= 0°C. The airflow through the rod surfaces is at T∞ = 0 °C with convection heat transfer coefficient h = 100 W/m2.K. (Hint: use table 3.4 in the lecture slides.)

(a) Express temperature T(x) along the fin and calculate the temperature at x=L/2. (5points)

(b) Determine the rate of heat transfer at the hot end of the fin (3 points) and calculate the fin effectiveness (2 points).

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